Recharging Air Conditioners – Straight from an HVAC Specialist

As our customers in Madison are turning on their AC Units, they’re discovering problems they didn’t know existed. The most common question we’ve had is about recharging AC unit Freon. We wanted to address it and explain our thoughts on recharging and exactly when it makes sense or doesn’t.

We all know that any air conditioner or furnace can fail at any time without warning. We live in a climate where we alternate hibernating and operating our mechanicals as we switch between heating and cooling seasons. Because we’ve come to depend on these units for comfort in our homes and businesses, we know all too well how that comfort can be compromised quickly when our mechanicals aren’t functioning properly.

AC Maintenance and Repairs

Many issues with air conditioners are a result of insufficient maintenance. The easiest repair is one that’s avoided altogether by keeping up on regular maintenance check-ups. In fact, if you haven’t been consistently maintaining your unit and notice your air conditioner starting to slack, a maintenance check-up may be just what you need to get your air conditioner back up to speed.  Some common problems homeowners experience that go beyond regular maintenance and should have checked out include: the compressor failing to turn on, the air not coming out cool enough, low airflow, and leaks.

Below are some ways you can diagnose air conditioning problems, descriptions of some common problems your air conditioning system may experience, and some special issues you should know about the refrigerant (Freon) in your system.

Ways to diagnose a problem:

  • Check fuse box or circuit breaker – First thing to do if your air conditioner is not functioning properly is to check the fuse box or circuit breaker that services the unit.  The fuse may need to be replaced or the circuit breaker reset.
  • Air conditioner turns on and off frequently – The compressor and fan controls may be worn out.
  • Unit turning on but not cooling – If your unit is turning on, but the air isn’t cooling efficiently, your refrigerant may be low.  You may also need to clean off the evaporator or condenser coils by brushing them off or vacuuming them. In addition, the filter may need to be replaced. Clogged, dirty filters block normal airflow and reduce a system’s efficiency considerably.
  • Insufficient Air Flow – Dirty air filters and/or closed or obstructed supply-air and return-air grilles may cause insufficient airflow through your system.
  • Leaks – These are usually associated with low refrigerant or a clogged drain pipe. Clogs can be fixed by clearing out the clogged pipe within the evaporator coil pan. Leaks should always be handled by a professional HVAC Contractor.

Common air conditioning problems:

  • Refrigerant Leaks –  If your air conditioner is low on refrigerant, either it was undercharged at installation or it leaks. If it leaks, simply adding refrigerant is not a solution. A trained AC technician should fix any leak, test the repair and then charge the system with the correct amount of refrigerant  Remember that the performance and efficiency of your air conditioner is greatest when the refrigerant charge exactly matches the manufacturer’s specification, and is neither undercharged nor overcharged. In addition, refrigerant leaks can be harmful to the environment.
  • Inadequate Maintenance –  If you allow filters and air conditioning coils to become dirty, the air conditioner will not work properly, and the compressor or fans are likely to fail prematurely.
  • Electronic Controls and Sensors Failure –  The electronic controls and sensor that cause your air conditioner, fan and condenser to kick off and on properly are often the first components to go.  Sometimes these sensors are merely knocked out of position causing the air conditioner to cycle constantly or behave erratically.  Fortunately, problems of this nature are easy to address compared to larger mechanical failures, and won’t cost you nearly as much.
  • Fan and Condenser Failure – Fan and condenser failure, on the other hand, can add up to some pretty pricey repairs. Replacing burnt-out fan motors is usually worth the expense in order to get your air conditioner up and running again, though a failed condenser can be a different story. A new condenser is the most expensive AC repair in the books, and depending on the age and efficiency of your current air conditioner, it might be a smarter investment to just upgrade to a newer unit.

Special Note About Air Conditioner Refrigerant (Freon): Contrary to popular belief, air conditioners do not consume refrigerant (Freon) as a car consumes oil, so under ideal conditions it would never need changing or filling. Therefore, a low Freon level indicates a leak which should be repaired before adding more. While most new system connections are welded to minimize leaks, many older units (8+ years) were connected with mechanical flared fittings, which can vibrate loose over the years, causing leaks.

Problems with Freon leaks:

  • Low Freon levels reduce efficiency of the air conditioner.
  • They can freeze the evaporator coil, causing it to literally ice up.
  • Freon is an Environmental Protection Agency (EPA) controlled substance, deemed hazardous if released into the environment.
  • The heart of the unit is the compressor, which is cooled by the refrigerant. Over time, low Freon levels can cause overheating and premature failure of the compressor, often requiring complete replacement of the compressor or the entire condensing unit. As mentioned earlier this is a very expensive proposition.
  • Always contact a HVAC professional when dealing with refrigerant (Freon).


Pharo Heating & Cooling is a full-service HVAC contractor in Madison. Our team provides top quality service for new construction and replacement furnace and air conditioner needs. For more information about annual furnace inspection or concerns, give us a call at 608-849-5410 or submit a contact form through our website.